Electron Configuration Video Lessons

Concept: Understanding Periodic Law

# Problem: The heaviest known alkaline earth metal is radium, atomic number 88.Find the atomic numbers of the as yet undiscovered next two members of the series.

###### FREE Expert Solution

We are asked to find the atomic numbers of the as yet undiscovered next two members after radium (atomic number = 88) in the alkaline earth metal series.

To do this, we shall follow these steps:

Step 1: Determine the electron configuration of radium (Ra).

Step 2: Determine the atomic number (i.e. identity) of the noble gas in the same period as radium (Ra).

Step 3: Determine the atomic number of the first member of the successor to radium (Ra) in the series.

Step 4: Determine the atomic number of the noble gas in the same period as the first member of the successor to radium (Ra) in the series.

Step 5: Determine the atomic number of the second member of the successor to radium (Ra) in the series.

Ground-state means that Radium is in its lowest energy form (not in an excited state). Radium also has no charge (neutral element) which means that no electrons are removed or added in the atom.

Neutral element:       Atomic number = # protons = # of electrons

▪ Atomic number = 88

▪ # of electrons = 88 e-

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###### Problem Details

The heaviest known alkaline earth metal is radium, atomic number 88.

Find the atomic numbers of the as yet undiscovered next two members of the series.